Electrolyte for electrolytic cells



July 1, 1924. 1,499,414

' J. SLEFIAN y ELECTROLYTE FOR ELECTROLYTIC CELLS Filed Nov. 20, 1920 WITNESSES: INVENTOR Joseph Slepicm.

ATTORNEY Patented July l, 1924.

UNITED STAT-Es PATENT oFFlca.

JOSEPH SLEPIAN, F SWISSVALE, PENNSYLVANIA, ASSIGNOR TO WETINGHOUE ELECTRIC & MANUFACTURING CPMPANY, A CORPORATION OF PENNSYLVANIA.

Enncrnon'rn ron nLEcrRoLY'rrc CELLS,"

Application med November 2o, 1920. serial No. 425,339.

To all wh'om t may concern:

Be it known that l, Josnrrr Sinnen, a citizen of the United States, and a resident of Swissvale, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electrolytes for Electrolytic Cells, of which the following is a specification.

This invention relates to electrolytes adapted 'for use in electrolytic cells of various types, such as electrolytic condensers, lightning arresters, rectifiers and the like. The present invention is an improvementover the invention described and claimed in my copending application, Serial No. 343,519, iled December 9, 1919, for electrolyte for electrolytic cells.

Electrolytic cells for the above stated and similar purposes are usually constructed with two sets of closely spaced electrodes consisting of closely folded and cut sheets of thin metal, such as aluminum, to present a large electrode-surface area in a small space.

' A suitable number of suchaelectrodes of opi electrolyte which has a posite polarity are' assembled in a container which is iilled with a suitable electrolyte.

Such electrolyte must be capable of forming a film on the surface of the metal electrede, which film should be impervious to temperature changes and be permanent over a considerable range of voltages. The cell thus formed should have a low power factor or low internal loss and should not devep any material amount of precipitates. eretofore, electrolytes for the above puroses have been defective in that the power actor of., the cell resulting from the use of these electrolytesV was too high, causing a relativel. *large power loss.- It was also practical y impossible to use such cell at a comparatively high temperature, since precipitates were formed at the higher temperatures which clogged up the spaces between the folds or laminations of the electrodes. The electrolyte described in ymy copending application above referred to, in part obviates these .disadvantages providing an ow power factor, and one which does vnot allow appreciable deposition of precipitates froml the electro? lyte. V

The present invention is` designed to more perfectly eliminate the disadvanta es hitherto encountered in electrol .of t

character, it being among the objects thereof y of a berate.

to provide an electrolyte which gives` a low power factor, is capable of use at high temperatures and does not deposit precipitates in any appreciable amount. l"

ln practising my invention, l provide an electrolyte of any suitable character, preferably of the type described in my copending application, and add to the same a small amount of a phosphorus compound, such as .a phosphate: Generally, my improved electates begin to form in a borax electrolyte which;"after .a while, becomeexcessive, rendering the cell ineliicient. Various phosphates have been proposed as electrolytes, since phosphates generally do not decompose and are remarkably free from preci itates. However, the power factor thereof c anges considerably with time. A solution of a phosphate at rst has a rather high power actor-whichrapidly decreases to a-minimum in a very short time, after which the power factor gradually increases until it becomes excessive. v

My invention combines the desirablel characteristics of both phosphates and borates, providing yan electrolyte which does not` deposit preci itates, and remains clean at all times, as oes a phosphate, and combines therewith the low vpower factor characteristic A composition of electrolyte which I have found to be eilicient for use in 'electrolytic cells is as follows:

Na3PC)4r 5.75 gr.,

vNal? 1 gr.,

H2O 1200 r. An electr ilyte embodying a phosphate and a borate is' practically aperfect electrolyte for electrolytic condon sers, lightning arresters, rectiliers and the like, especially when afluoride is added,- to the solution which is alkaline. I have found that a ce f containing an electrolyte'of this kind may be operatedy continuously at or above`90O C., or practically the boilingpoint of the solution, with no deterioration of electrolyte, film, or electrode, whereas, with prior electrolytes, a temperature of 40 C. was probably the maximum that could be utilized. My cell has a power factor between 4% and `5% at thehigh temperature, being equally as efiioient as a borate in this respect and having the added advantages that the electrodes re- `main remarkably clean, allowing a freev circulation ofthe electrolyte between the folds of the electrodes.

It is obvious that my invention, although ldescribed in connection with a 'specific emy bodiment thereof, is not limited to the details or specific proportions set forth, but resides essentially in the use of a phosphate invoonjunction with any electrolyte of the mm-forming type,A generally includinga '.iborate. v l I claim as my invention: j 1. An electrolyte for electrolytic condenslers, vlightning arresters, rectiiiers, and the jgslikefwmprismg Ipliosphate. j 4

2. An' electrolytelfor elcctrolyticd condensers, lightning arresters1 rectiiiers, andthe like comprising a borate vand a phosphate.

a boron compound and ,ak

sodium phosphate `5.7 5 parts, 'sodium fluoride 1 part and water 1200 parts.

like comprising a boron compound and a phosphate in alkaline solution.

7. An electrolyte for electrolytic condensers, lightning arresters, rectiiiers and the like comprisingav borate and va alkaline solution.

8. An electrolyte for electrolytic condensphosphate in sers, lightning arresters, rectifiers and the like/ comprising a borate, a phosphate and al uoride in alkaline solution.

In test'intlony-` whereof, I have hereunto 55 6. An electrolyte for electrolytic condensl I, ers, lightning arresters, rectifiers, and the 

